Ibibo Group / Goibibo — Technical issue happened and flight ticket not generated. Later only partial amount was refunded.

I had made a multi-city flight ticket booking on March 4th for travel from Zurich to Santorini via Athens. I had made a payment of Rs.90, 399 for the same. However, the booking failed and the ticket was not generated. Half an hour later, I got a call from Goibibo customer care stating that a technical glitch had happened, the ticket had not been generated and it would be refunded. But I have received a refund of Rs.72, 450 only. I had contacted the support multiple times and they said they have opened a refund claim. It's been more than a week and I still haven't received the remaining refund amount of Rs.17, 949. Failed booking id - GOFLINTIOSG3E7O18W7235.